Validity of a tool designed to assess the preventability of potentially preventable hospitalizations for chronic conditions.

BACKGROUND: Potentially preventable hospitalizations (PPH) are defined as unplanned hospital admissions which could potentially have been prevented with the provision of effective, timely outpatient care. To better understand and ultimately reduce rates of PPH, a means of identifying those which are actually preventable is required. The Preventability Assessment Tool (PAT) was designed for use by hospital clinicians to assess the preventability of unplanned admissions for chronic conditions. OBJECTIVE: The present study examined the ability of the PAT to distinguish between those unplanned admissions which are preventable and those which are not, compared to the assessments of an Expert Panel. METHODS: Data were collected between November 2014 and June 2017 at three hospitals in NSW, Australia. Participants were community-dwelling patients with unplanned hospital admissions for congestive heart failure, chronic obstructive pulmonary disease, diabetes complications or angina pectoris. A nurse and a doctor caring for the patient made assessments of the preventability of the admission using the PAT. Expert Panels made assessments of the preventability of each admission based on a comprehensive case report and consensus process. RESULTS: There was little concordance between the hospital doctors and nurses regarding the preventability of admissions, nor between the assessments of the Expert Panel and the hospital nurse or the Expert Panel and the hospital doctor. CONCLUSIONS: The PAT demonstrated poor concurrent validity and is not a valid tool for assessing the preventability of unplanned hospital admissions. The use of Expert Panels provides a more rigorous approach to assessing the preventability of such admissions.

Effect of unilateral endobronchial valve insertion on pulmonary ventilation and perfusion: a pilot study.

BACKGROUND AND OBJECTIVE: The effects of bronchoscopic lung volume reduction (BLVR) on pulmonary ventilation and perfusion are incompletely understood. In this pilot trial, we investigated serial changes in regional ventilation and perfusion following unilateral endobronchial valve placement in COPD patients with heterogeneous emphysema. METHODS: At baseline and at days 30 and 90 following BLVR, subjects underwent lung function, 6MWD and St George's Respiratory Questionnaire. Ventilation and perfusion scintigraphy were performed to quantitate and serially compare regional differences. RESULTS: Six out of eight subjects completed the study; all had endobronchial valves targeting their left upper lobe. At day 90 post-BLVR, there was a trend towards an increase in FEV(1) and a mean reduction in St George's Respiratory Questionnaire score of nine units. In the targeted left upper zone there was reduced ventilation and perfusion. Ventilation and perfusion to the right lung; and specifically the right lower zone, significantly increased. CONCLUSIONS: There appears to be redistribution of ventilation and perfusion to the contralateral lung following endobronchial valve placement. This may be of importance when assessing patients for unilateral BLVR. Selecting patients with heterogeneous disease is emphasized, taking into consideration not just comparison between upper and lower lobes, but between left and right lungs. A larger trial is currently underway, guided by these findings.

Glossopharyngeal insufflation causes lung injury in trained breath-hold divers.

BACKGROUND AND OBJECTIVE: Glossopharyngeal insufflation (GI) is a technique practised by competitive breath-hold divers to enhance their performance. Using the oropharyngeal musculature, air is pumped into the lungs to increase the lung volume above physiological TLC. Experienced breath-hold divers can increase their lung volumes by up to 3 L. Although the potential for lung injury is evident, there is limited information available. The aim of this study was to examine whether there is any evidence of lung injury following GI, independent of diving. METHODS: Six male, competitive breath-hold divers were studied. CT of the thorax was performed during breath-holding at supramaximal lung volumes following GI (CT(GI)), and subsequently at baseline TLC (CT(TLC)). CT scans were performed a minimum of 3 days apart. Images were analysed for evidence of pneumomediastinum or pneumothorax by investigators who were blinded to the procedure. RESULTS: None of the subjects showed symptoms or signs of pneumomediastinum. However, in five of six subjects a pneumomediastinum was detected during the CT(GI). In three subjects a pneumomediastinum was detected on the CT(GI), but had resolved by the time of the CT(TLC). In two subjects a pneumomediastinum was seen on both the CT(GI) and the CT(TLC), and these were larger on the day that a maximal GI manoeuvre had been performed. The single subject, in whom a pneumomediastinum was not detected, was demonstrated separately to not be proficient at GI. CONCLUSIONS: Barotrauma was observed in breath-hold divers who increased their lung volumes by GI. The long-term effects of this barotrauma are uncertain and longitudinal studies are required to assess cumulative lung damage.